Numerous techniques are employed for the administration of “medical liquids” (e.g. liquid medication and flush solutions) to a patient. In particular, where repeated medication infusions are required, medical liquids are often administered via the use of a vascular access catheter that is fluidly interconnected or interconnectable to one or more medical liquid sources via an associated tubing line set. Typically, the catheter is inserted into the vein of a patient and left there for multiple intravenous (IV) infusions during an extended course of medication therapy. By way of example, the time period between IV drug infusions may be between about 4 to 24 hours, wherein the IV liquid medication source is typically replaced after each dose infusion. In the course of extended medication therapy a given tubing line set may be repeatedly employed, and a number of tubing line sets may be successively employed. For example, it is typical to replace a given tubing line set every two or three days.
During extended therapy applications, a desirable practice is to disconnect the vascular catheter from a medical liquid source and tubing line set between infusions. In this regard, most patients receiving IV medication therapy are ambulatory to some degree and benefit from not being continuously connected.
In conjunction with the repeated connection/disconnection of a vascular catheter and liquid medication source and tubing line set, it is usual practice to purge the vascular catheter with a flush solution (e.g. a saline solution) prior to and at the completion of a given liquid medication infusion. Pre-infusion flushing verifies that the vascular catheter is primed and clear of obstructions. Post infusion flushing not only flushes through any remaining liquid medication to achieve the desired therapeutic effect, but also reduces any chance that the vascular catheter may become blocked in-between infusions, e.g. by a blood clot that may otherwise form in the vascular catheter. In relation to infusion procedures, it is also common practice to verify the proper functioning of a vascular catheter via aspiration. This is typically done prior to pre-infusion flushing and after liquid medication infusion. The procedure entails using the flush solution syringe or liquid medication syringe to drain a small amount of a patient's blood through the vascular catheter, thereby permitting visual verification of proper vascular catheter functionability, then advancing the blood back through the vascular catheter using the syringe. By way of example, such procedure assures that the vascular catheter is not blocked by a blood clot and is otherwise properly inserted into a patient's vascular system.
A number of approaches are currently utilized for the noted flushing procedures. Such techniques generally entail the usage of flush solutions packaged in large volume, multi-dose reservoirs (e.g. about 250 ml. or more) or pre-filled unit dose syringes (e.g. having volumes of 2, 3, 5 or 10 ml.).
Where a unit dose syringe is utilized, medical personnel must generally remove the syringe from packaging, remove a cap from the syringe, remove any air in the syringe, swab a vascular catheter access port with an antibacterial material, interconnect the syringe to a vascular catheter access port, optionally aspirate the vascular catheter, advance the syringe plunger to infuse the flush solution (e.g. at a rate of about 5 to 10 ml. over about 15 to 30 seconds), remove the syringe from the vascular catheter access port and discard the used syringe with its wrapper. As may be appreciated, such steps may need to be repeated numerous times over the course of extended medication therapy, e.g. after each infusion and vascular catheter access port reconnection, thereby entailing significant medical personnel time and resulting in substantial medical waste. Further, while unit dose syringes provide good sensitivity for aspiration purposes they are not particularly pressure sensitive for flushing purposes.
Where multi-dose flush solution reservoirs are employed, medical personnel typically utilize an empty unit dose syringe to draw the flush solution from the reservoir, then follow the same basic procedure noted above in an administering the flush solution. Again, such procedure may be followed a number of times during a medication therapy. Further, contamination concerns may arise when a unit dose syringe is filled from a multi-dose reservoir at the point of use. To address such concern, unit dose syringes are often filled from a multi-dose reservoir within a pharmacy department of a medical care facility utilizing a hepa-filter air hood. However, significant syringe handling is required. Moreover, labeling becomes a further need when a delay is expected between the filling of a unit dose syringe and the usage of the filled syringe.